TOXINES OF THE TUBERCLE BACILLUS. 251 



digestion of various albumins give the same reaction in tubercular 

 guinea-pigs. The injection of milk, lactic acid, ricin all give a similar 

 result. Before the discovery of tuberculin, Gamaleia had found that 

 tubercular animals were very susceptible to the toxines of the vibrio 

 Metchnikovi, and later Metchnikoff found that a similar susceptibility 

 existed towards the toxines of the bacillus of fowl cholera. Buchner 

 found that a group of albuminous bodies which he called proteines, and 

 which he extracted from the bodies of the B. anthracis, B. mallei, and 

 B. prodigiosus, produced the tuberculin reaction, and he considered 

 that the active body in tuberculin was probably of the same nature, and 

 had a similar source. There is, however, no evidence that the sub- 

 stances so derived from different bacteria are identical. While the 

 tuberculin reaction has thus been obtained with other bodies besides 

 tuberculin, a similar reaction has taken place when tuberculin has been 

 injected into persons suffering from diseases other than tubercle, e.g. , 

 cancer, sarcoma, syphilis. Further investigations on this subject are 

 thus required. 



The Toxines of the Tubercle Bacillus. Koch's work 

 on tuberculin showed that there could be separated from 

 tubercle cultures substances the necrotic action of which 

 on certain tissues was capable of explaining a great patho- 

 logical feature of tuberculosis. The inquiries which this 

 fact stimulated were first directed towards finding out what 

 the substance was to which tuberculin owes its action. 

 Hunter stated that tuberculin consists chiefly of (i) 

 albumoses, chiefly proto- and deutero-albumose, with small 

 quantities of hetero-albumose and a trace of dysalbumose ; 

 (2) alkaloidal substances, two of which can be obtained in 

 the form of platinum compounds of their hydrochlorate 

 salts ; (3) extractives, mucin, inorganic salts, etc. He 

 prepared two modifications of tuberculin, one of which con- 

 tained all that could be precipitated by 70 per cent alcohol, 

 and the other all that was left. The former, which of 

 course contained a larger proportion of albumoses, produced 

 less fever than the latter. From this fact it appeared that 

 the necrotic action on the tissues and the fever-producing 

 effects were not necessarily caused by the same body in 

 tuberculin. The most complete analyses of tuberculin were 

 carried out by Kiihne, who generally confirmed Hunter's 

 results, except that he found peptone also present. He 



